The 1991 Yamaha YZ250 is a potent 2-stroke motocross motorcycle renowned for its performance and agility. As a significant model in Yamaha's competitive motocross lineage, it was engineered to excel in the demanding 250cc class, directly competing with other leading brands of its era. Its strengths lie in its powerful engine, capable suspension, and lightweight chassis, making it a formidable machine for racing and off-road enthusiasts. The YZ250's design reflects Yamaha's extensive motorsports heritage and continuous development in off-road competition.

This service manual provides comprehensive guidance for the maintenance, repair, and troubleshooting of the 1991 Yamaha YZ250 motorcycle. It covers all essential systems, including the engine, transmission, suspension, brakes, and electrical components, offering detailed procedures for routine maintenance, diagnostics, and component overhauls. With in-depth technical specifications, torque values, and clear instructions, this manual is an indispensable resource for owners, mechanics, and technicians seeking to ensure optimal performance, reliability, and longevity of their YZ250.